Preparation and Characterization of Essential Oils Chitosan Nanoparticles: Physical, Structural, and Antioxidant Activity

Abstract

One of the recent trends in food industry is the application of natural antioxidant agents. In this study, cinnamon, clove buds, laurel, basil and lemongrass essential oils have been extracted and encapsulated in chitosan nanoparticles using a two-step technique of emulsion-ionic gelation of chitosan with sodium tripolyphosphate (TPP). The obtained nanoparticles exhibited a regular distribution and spherical shape as observed by scanning electron microscopy (SEM). As determined the encapsulation efficiency (EE) and loading capacity (LC) of tested essential oils loaded chitosan nanoparticles were about (1.78, 35.63, 14.33, 0.97, 2.27)% and (0.94, 19.01, 5.06, 0.66, 1.51)% respectively, with a chitosan/essential oil ratio of 1:1 (w/w). In vitro release studies showed an initial burst effect followed by a slow essential oil release. The active ingredients of tested essential oils were prevented from being volatilized, significantly improving the chemical stability, so the scavenging activity of encapsulated EOs on DPPH radicals was in the range of 0.58%, 1.36%, 0.16%, 0.29% and 0.14% respectively. This technique could improve the efficiency of essential oils in food products and a delivery system for novel applications such as active packaging.